1. Field of the Invention
The present invention relates to a shift lever operating apparatus for an automatic transmission in an automotive vehicle and the like, and more particularly to a shift lever operating apparatus for an automatic transmission which is arranged in a side portion of a steering column fixed to a vehicle body end and connected to a key interlock mechanism.
2. Description of the Related Art
FIGS. 1-3 show a typical shift lever operating apparatus for an automatic transmission designed in accordance with the conventional prior art. The shift lever operating apparatus for an automatic transmission is connected to an automatic transmission through a transmitting member including a control tube 1 rotatably provided in a side portion of a steering column apparatus (not shown) and a shift lever 2 axially attached to a socket la provided in the control tube 1 and projecting so as to freely stand in an axial direction by a mounting pin 2a. A recess portion 3a engages a spherical engaging portion 2b formed in a base portion of the shift lever 2 and is fixed to a side portion of the steering column apparatus with a compression rod 3 sliding within the control tube 1 in an axial direction in accordance with an operation of the shift lever 2. A return spring 4 biases the compression rod 3 toward the shift lever 2 in the axial direction. A selector member 5 is fixed to the compression rod 3 and a plurality of detent grooves 6a in a detent bracket 6 selectively engage a detent portion 5c formed in the selector member 5. The detent bracket 6 rotatably supports a lower end of the control tube 1.
The selector member 5 is inserted through an insertion hole 3b formed through a middle portion of the compression rod 3 in a diametrical direction. A portion projecting from an outer peripheral surface of the compression rod 3 is slidably inserted through an oblong hole 1b formed by extending therethrough in a diametrical direction along an axis of the control tube 1.
The selector member 5 is fixed to the compression rod 3 by pressing two mounting pins 5a through the control tube 1 from a pair of aligned oblong holes 1c formed in control tube 1 in a diametrical direction along an axis perpendicular to oblong holes 1b. Both ends of each pin 5a project from the outer peripheral surface of the control tube 1 and pass through two mounting holes 3c and 5b formed in the compression rod 3 and the selector member 5 respectively. In addition, the compression rod 3 is structured to integrally rotate with the control tube 1.
The detent bracket 6 is oriented perpendicular to the control tube 1 in such a manner that the middle portion of the control tube 1 is inserted through it. A lock member 7 restricts movement in a selecting direction of the selector member 5 when the selector member is at a parking position, that is, in the direction of an arrow R shown in FIG. 1. Lock member 7 is axially attached to the detent bracket 6 by a mounting shaft 7a. 
The apparatus is structured such that the selector member 5 is brought into contact with the lock member 7 and the detent 5c of the selector member 5 does not come out from the parking position groove, that is, the shift lever 2 can be locked at the parking position even by operating the shift lever 2 in a select direction, that is, a direction of an arrow S when the selector member 5 is at the parking position, that is, the detent portion 5c of the selector member 5 engages with a parking position groove of the detent groove 6a. 
In the shift lever operating apparatus for an automotive vehicle described above, since the selector member 5 is arranged in the middle portion of the compression rod 3, it is difficult to mount the selector member 5 to the compression rod 3. Further, since the detent groove 6a engaging with the selector member 5 is provided at the middle portion of the control tube 1 in the detent bracket 6 supporting the lower end of the control tube 1, the detent bracket 6 is made large.
Further, when the selector member 5 is at the parking position and the shift lever 2 is locked, forceful operation of the shift lever 2 in a shift direction, for example, the direction of an arrow T (see FIG. 2), places a great load on each of the end surfaces of oblong holes 1b and 1c in the control tube 1 through the selector member 5 and pins 5a. The great load presents a risk that a portion near the oblong holes 1b and 1c will become deformed and a sliding motion of the selector member 5 is not going to be smooth. Thus, it is necessary to make the control tube 1 and the detent bracket 6 very thick to thereby prevent the portion near the oblong holes 1b and 1c and the portion near the detent groove 6a from deforming. Accordingly, the weight of the whole apparatus is increased and the apparatus becomes very large.
Further, in the shift lever operating apparatus for an automatic transmission described above, operation of the shift lever 2 in the selecting direction places a great load on compression rod 3 in the axial direction. The great load acts on the lock member 7 and mounting shaft 7a through the selector member 5 when the shift lever 2 is at the parking position thus, a thick large-sized and strong member is used for the lock member 7 and mounting the shaft 7a to sufficiently stand the great load. The lock member 7 rotates from a locked position, where the lock member 7 engages with the selector member 5, to an unlocked position, where the lock member 7 disengages with the selector member 5, by driving a solenoid as an actuator (not shown).
Accordingly, the whole apparatus becomes large and the weight thereof becomes increased. Further, since the mass of an inertia in the lock member 7 increases in accordance with an increase of the weight, when stepping on a brake to cancel an excitation of the solenoid to permit shifting the shift lever 2 from the parking position to another position rapid operation of the shift lever 2 delays rotation from a locked position of the lock member 7 to an unlocked position. In other words, the responsiveness of the lock member 7 is decreased, so that a lock removal by the lock member 7 cannot be quickly performed.
Still further, since the lock member 7 is mounted to the detent bracket 6 by the mounting shaft 7a, the space necessary for mounting and operating the lock member 7 is large, and the whole apparatus becomes large.
Furthermore, in this kind of shift lever operating apparatus for an automotive vehicle, when the shift lever is shifted to the parking position it is locked by the lock member. The lock member rotates from the locked position to the unlocked position in response to the solenoid as the actuator, as stated above.
Accordingly, it is structured so that when the shift lever is shifted to the parking position, the solenoid becomes electrified so as to rotate the lock member to the locked position, thereby locking the shift lever in the parking position. When the brake is stepped on at a time of starting the vehicle, the solenoid becomes de-electrified so as to rotate the lock member to the unlocked position, thereby shifting the shift lever from the parking position to the other position.
Further, an engine key can be removed from a key interlock mechanism only when the shift lever is shifted to the parking position. When in a parked state and the engine key is taken out the key lock lever, which is arranged between the lock member and the key interlock mechanism, is locked and the lock member, which is disposed at the locked position, is prevented from rotating in the unlocked direction by the locked key lock lever.
Then, it is structured such that when the shift lever is moved from the parking position to another position, a lock of the key lock lever is canceled by inserting the engine key into the key interlock mechanism and operating it, thereby rotating the lock member in the unlocked direction.
In such a system when an electric system malfunction occurs at the time of changing the shift lever from the parking position to another position it is possible that the solenoid will not operate. When this occurs, it is impossible to rotate the lock member to the unlocked position, so the shift lever is kept in the parking position.
Further, when the shift lever is changed from the parking position to another position, it is necessary to insert the engine key into the key interlock mechanism and operate it, thereby canceling the lock of the key lock lever. However, sometimes it is desirable to move the automotive vehicle by human power without using the engine key, thus an alternative design that would permit this would be beneficial.
The present invention has been achieved with such points in mind.
It is therefore an object of the present invention to provide a shift lever operating apparatus for an automatic transmission that has a compact and light control tube and detent bracket, that makes it easy to mount a selector member and the detent bracket, and that makes it easy to mount a control tube to the detent bracket.
Another object of the present invention is to provide a shift lever operating apparatus for an automatic transmission that is more compact by making a smaller lock member and a smaller space for mounting and operating the lock member. It is also an object to make a mounting structure of the lock member simpler.
Still another object of the present invention is to provide a shift lever apparatus for an automatic transmission that can cancel a shift lock of the shift lever shifted to the parking position by a manual operation without an engine key.
In order to achieve the objects mentioned above, in accordance with a first aspect of the present invention, there is provided a shift lever operating apparatus for an automatic transmission, comprising: a control tube rotatably supported in a side portion of a steering column; a shift lever axially attached to the control tube in such a manner as to stand in an axial direction; a compression rod inserted into the control tube, the compression rod moving in an axial direction in accordance with an operation of the shift lever and integrally rotating with the control tube; a return spring pressing the compression rod in the axial direction toward the shift lever; a selector member fixed to the compression rod; a detent bracket having a plurality of detent grooves with which a detent portion formed in the selector member selectively engages and fixed to a vehicle body end, wherein the detent bracket is perpendicular to the control tube and rotatably supports an end portion apart from the shift lever of the control tube; the detent groove is formed on the same surface as the supporting portion where the detent bracket supports the end portion of the control tube; and the selector member is fixed to an end portion of the compression rod projecting from the end portion apart from the shift lever of the control tube.
In accordance with a second aspect of the present invention, as it depends from the first aspect, the selector member is held by an arm member fixed to the end portion apart from the shift lever of the control tube, and integrally rotated with the control tube.
In accordance with a third aspect of the present invention, as it depends from the second aspect, a holding portion of the arm member is arranged near the detent bracket.
Then, in the invention in accordance with the first aspect structured in the above manner, since the detent bracket is perpendicular to the control tube and rotatably supports the end portion apart from the shift lever and the detent groove is formed on the same plane as the supporting portion, a rigidity can be improved in comparison with the conventional structure in which the detent bracket is arranged in the middle portion of the control tube, and the detent bracket can be made compact.
Further, since the selector member is fixed to the end portion of the compression rod projecting from the end portion apart from the shift lever of the control tube, it is not necessary to form an oblong hole on the outer peripheral surface of the control tube, so that the control tube can be easily processed and the rigidity can be widely improved. Accordingly, the control tube can be made compact and thin, that is, light. Further, the structure of mounting the selector member to the compression rod can be widely made simple. At a time of assembling, since the parts can be inserted into the compression rod from the end portion close to the shift lever one by one, assembly is improved.
In the invention in accordance with the second aspect, since the selector member is held by the arm member fixed to the end portion apart from the shift lever of the control tube and integrally rotated with the control tube, an operation of the shift lever can be properly transmitted to the selector member.
Further, since the selector member is held by the holding portion of the arm member, the strength can be improved with restricting the selector member from deforming, so that the selector member can be made compact and thin, that is, light.
In the invention in accordance with the third aspect, since the holding portion of the arm member is arranged near the detent bracket, the strength can be widely improved, the deformation of the selector member can be further restricted and the selector member can be further made thin and light.
In accordance with a fourth aspect of the present invention, there is provided a shift lever operating apparatus for an automatic transmission, comprising: a control tube rotatably supported in a side portion of a steering column; a shift lever axially attached to the control tube; a compression rod inserted into the control tube, the compression rod moving in an axial direction in accordance with an operation of the shift lever and integrally rotating with the control tube; a return spring pressing the compression rod in the axial direction toward the shift lever; a selector member fixed to the compression rod; a detent bracket having a plurality of detent grooves with which the selector member is selectively engaged and perpendicular to the control tube and rotatably supporting the end portion opposite the shift lever of the control tube; a lock member having a lock portion engaging with the selector member positioned at the parking position so as to restrict the operation of the shift lever in the select direction; and an actuator rotating the lock member from a locked position engaging with the selector member to an unlocked position at which the engagement is canceled, wherein the selector member has an engaging portion located apart from a side surface of the detent bracket with a predetermined interval and perpendicular to the control tube; the lock member has a base portion slidably brought into contact with the one side surface of the detent bracket and rotatably supported in a coaxial manner with the control tube; the lock portion is mounted so as to project from an outer peripheral surface of the base portion; and the lock portion moves between the engaging portion of the selector member and the one side surface of the detent bracket by driving the actuator, thereby preventing the selector member from moving in the axial direction.
Then, in the invention structured in the above manner, since it is structured such that the lock portion of the lock member moves between the one side surface of the detent bracket and the engaging portion of the selector member, thereby preventing the selector member from moving in the axial direction, the load acting on the lock member through the selector member by operating the shift lever at a time of shifting the shift lever from the parking position is directly input to the detent bracket, so that it is sufficient that the lock member has a strength enough to stand the compression force.
Accordingly, the lock member can be made compact and light, the responsiveness of the lock member can be improved by making a mass of an inertia in the lock member small, and the cost can be reduced. Further, since the lock member is slidably brought into contact with the one side surface of the detent bracket and rotatably supported in a coaxial manner within the control tube, the space for mounting and operations of the lock member can be made small, and the structure of mounting the lock member can be made simple.
In accordance with a fifth aspect of the present invention, there is provided a shift lever operating apparatus for an automatic transmission, comprising: a control tube rotatably supported in a side portion of a steering column; a shift lever axially attached to the control tube in such a manner as to stand in an axial direction; a compression rod inserted into the control tube, the compression rod moving in the axial direction in accordance with an operation of the shift lever and integrally rotating with the control tube; a selector member fixed to the compression rod; a detent bracket having a plurality of detent grooves with which the selector member selectively engages and rotatably supporting an end portion apart from the shift lever of the control tube; a lock mechanism interlocking with a key interlock mechanism structured such that an engine key can be inserted to and taken out only at a time of shifting the shift lever to a parking position, and preventing the shift lever from moving from the parking position to the other position in response to a brake, wherein the lock mechanism, comprises: a lock member restricting a selecting operation of the shift lever by engaging with the selector member positioned at the parking position, the lock member rotatably supported in a coaxial manner with the control tube in such a manner as to move from a lock position engaging with the selector member to an unlock position at which the engagement is canceled, the lock member connected to an actuator interlocking with the brake; a first key lock lever rotatably and axially attached by the detent bracket, the first key lock lever formed in such a manner as to freely engage with the selector member positioned at the parking position at a side apart from the selecting direction, the first key lock lever interlocked with the key interlock mechanism through a transmitting member a second key lock lever axially attached to the same axially attaching portion of the first key lock lever, the second key lock lever connected in such a manner as to integrally rotating with the first key lock lever by urging means, the second key lock lever being formed in an engageable manner so as to restrict a rotation to the unlock position with respect to the lock member positioned at the lock position in a state that the first key lock lever is engaged with the selector member; and a forcibly lock canceling mechanism forcibly canceling an engagement between the second key lock lever and the lock member positioned at the lock position by a manual operation, the forcibly lock canceling mechanism forcibly rotating the lock member positioned at the lock position to the unlock position by another manual operation.
Further, in accordance with a sixth aspect, as it depends from the fifth aspect, in the shift lever operating apparatus for an automatic transmission, the forcibly lock canceling mechanism further comprises: second key lock lever forcibly driving means provided in the second key lock lever in such a manner as to forcibly cancel the second key lock lever engaging with the lock member positioned at the lock position by a manual operation; and actuator forcibly driving means provided between the second key lock lever and the actuator in such a manner as to forcibly drive the actuator in an interlocking manner with a drive operation of the second key lock lever forcibly drive means and rotate the lock member positioned at the lock position to the unlock position.
Then, in the invention in accordance with the fifth aspect, as mentioned above, since the lock member positioned at the lock position can be forcibly rotated to the unlock position by the forcibly lock canceling mechanism when the shift lever is locked positioned at the parking position, the shift lock of the shift lever shifted to the parking position can be canceled and the shift lever can be changed from the parking position to the other positions even in the case that the engine key is not present, or the actuator is fixed due to a trouble in an electric system and the like.
Further, in the invention in accordance with the sixth aspect, since an engagement between the lock member positioned at the lock position and the second key lock lever can be forcibly canceled by a manual operation by means of the second key lock lever forcibly driving means, the shift lock of the shift lever shifted to the parking position can be canceled even in the case that the engine key is not present. Still further, since the lock member positioned at the lock position can be forcibly rotated to the unlock position by a manual operation by means of the actuator forcibly driving means, the shift lock of the shift lever shifted to the parking position can be canceled even in the case that the actuator does not drive due to the trouble in the electric system and the like.